An association of primary hyperparathyroidism and non medullary thyroid carcinoma.

A 40-year-old woman was admitted because of long-lasting asymptomatic hypercalcaemia. About 2 years earlier she underwent thyroidectomy and further 131 I therapy because of well-differentiated non medullary thyroid carcinoma. On admission biochemical data and hormonal values (serum calcium, serum phosphorus, i-PTH) were consistent with primary hyperparathyroidism; ultrasonography, computed tomography, thallium-technetium scintiscanning disclosed right paratracheal mass; on surgical procedure a right parathyroid adenoma was removed. The coexistence of non medullary thyroid carcinoma and primary hyperparathyroidism is rare: the prior 131 I therapy might be linked to subsequent development of parathyroid adenoma.